Great and fun game, i loved the upgrade part and the shop, these systems typically takes time and you managed to put it together in less than a week very nice!.
The mechanics are cool and everything, but i have some comments
maybe consider adding a temporary invulnerability state for a few seconds after taking the first hit and destroying your shield, as what usually happens that i get hit with two objects exactly at the same spot and i get completely destroyed, which makes the shield concept obsolete.
Another thing maybe make the space ship more responsive the input , i notice that it takes some time to start moving after i press on the keyboard.
But overall this is a great game , with a good potential :)
Great Job!
Don't forget to checkout our game :)